The adjusting and aligning of the upper and lower rolls of horizontal and universal roll stands is necessary, in particular, after the rolls have been changed. In this connection, it is important that the horizontal rolls be adjusted so that they are precisely aligned with the roll center plane and have a strictly parallel relationship to it. Traditionally, the adjustment was either effected manually, which is very time consuming and was dependent on the skill of the operators, or automatically, by such methods as those described, for instance, in Federal Republic of Germany DE 35 01 622 C2, incorporated herein by reference, which describes the automatic alignment of a universal roll stand.
In the method described in DE 35 01 622 C2, the lower roll is first brought to the roll center, in which connection optical detection devices may be used to determine the position of the lower roll. The upper roll is then moved at creep speed towards the lower roll, and is applied against the latter. If the two rolls are not parallel, any possible oblique orientation of the upper roll with respect to the lower roll is detected by measuring a difference in roll pressure at either end of the upper roll, by means of pressure measurement sensor modules arranged on both sides of the upper roll. The position of the upper roll is corrected on the basis of these readings.
The method of DE 35 01 622 C2 is unsuitable for precise horizontal alignment, since the position of the upper roll is oriented relative to the position of the lower roll, and is thus subject to horizontal misalignment if the lower roll has not been accurately positioned horizontally. In this way, while the method allows the automatic alignment to produce a parallel roll nip, the nip as a whole can however be inclined out of the rolling plane. From Federal Republic of Germany DE 24 54 896 A1, incorporated herein by reference, a method is known for the adjustment of a parallel, open roll nip, in which equal forces are applied by the adjustment devices onto both ends of the roll are applied. In order to balance the roll, intermediate pieces, such as shims, which cooperate with the chocks, are provided on both sides of the housing.